Buy and hold without a monthly account/platform fee. ABSA worldtrader allows you to deposit foreign currency directly without incurring conversion fees and also facilitates the registration for globetax to claim back 10% on dividend withholding tax charged for my US portfolio. So the actual platform is overkill for what I want, but the entire solution is actually pretty decent (strange for ABSA to get something right).

NFEMOM is an interesting one - I considered it for some local diversification. Compared to the Nedgroup Entrepeneur and Coronation Top20 funds it is doing exceptionally well, but with a much lower TER (over 5 years it lost less than 2% compared to NEDENTA and outperformed CORTP20). When the transaction costs are included though, NFEMOM feels VERY expensive for an ETF. In terms of holdings it is quite different from the two active funds I mentioned. NFEMOM is tilted towards basic materials/resources whereas NEDENTA is slightly more balanced (with regards to the other sectors: ~20% in Industrials, Consumer Services and Financials. 10% in Health Care and Consumer Goods). NEDENTA only has 2% in basic materials compared with 52% in NFEMOM. So it could be a nice supplement to NEDENTA - not a lot of overlap. I will look at it again next year.

I could have probably gone with a money market account, but I wanted to keep the TFSA itself balanced as well according to my AA. That way I can manipulate my taxable investments without having to chop and change the TFSA as well. So that leaves normal bonds and inflation linked bonds. I don't want bonds for growth, I want them to help me sleep at night when 2000 or 2008 happens again and the market drops by 60+%. So I am not concerned about the yield, but it would be nice if they at least beat inflation (hence inflation linked bonds).
The two main alternatives to STXLIB are the Ashburton Inflation ETF (ASHINF) and NewFunds/ABSA ILBI (NFILBI). STXILB is a total return fund like NFILBI, so interest/coupons are reinvested automatically. STXILB will (probably) do that for less cost than NFILBI (~0.6%). At the moment the transaction cost for STXILB is unknown due to its age, but the TER is 0.25% vs ABSA's 0.43%. Although they don't track the same index, the holdings are virtually identical.
Bond funds are normally difficult to choose - I will have a look again next year when I re-rebalance and invest for 2018.

I believe in buy/hold when it comes to investment. I have the following three funds in my TFSA portfolio:
60% DBXWD
20% PTXTEN
20% STXILB
I max out my allowance over three months ("dollar cost averaging") and re-balance all my investments yearly to maintain my AA.

The ABSA fees are different depending on which accounts you add to your profile. Only the Smart Account (and managed accounts) have a monthly fee. The TFSA, ETF Only and Worldtrader work on brokerage and custodian fees. So if you don't want to buy ordinary shares on the JSE you don't need the Smart Account. I recently started using the ABSA platform and although it is not as polished as Standard Bank's it is pretty decent and cost effective for my investment "style".

My choice would have been a taxable account in his name - just to remove/reduce the capital gains burden when cashing it out. With the added responsibility to teach him good financial discipline and not have him squander the investment. You have 18 years for that
I would also say that it is very important to ensure that this "secondary investment" does not dramatically influence your ability to save for your own retirement. There are always the options of a study loan and bursaries to make up for any shortfall.

My AA is between 75/25 and 80/20. The majority of my portfolio is offshore with active funds (mostly Orbis) and passive trackers (Vanguard/Blackrock), but I have some funds in SA (also split between active funds (Coronation, Allan Gray) and passive funds/ETFs.
In my SA ETF portfolio I went for a simple three fund portfolio with a buy/hold strategy:
DBXWD - 60%
PTXTEN - 20%
STXILB - 20%
I chose:
1. DBXWD over DBXUS for increased diversification and lower TER. I have a lot of US exposure in my overall portfolio, so I preferred to go a bit broader here. The Euro zone is currently struggling (as is Asia), but I still feel it is a better long term investment.
2. PTXTEN over PTXSPY (and similar listed property options from Stanlib and Satrix) due to liquidity/spread. In my overall portfolio I have a smaller allocation to (mostly global) property, but since I went with a global equity fund as my core in this portfolio I increased the property allocation to get more SA exposure.
3. STXILB over the other listed ILB indexes based on EAC. Ashburton (ASHINF~0.5%) and Newfunds/ABSA (NFILBI, ~0.6%)
I didn't chose:
1. Narrow, sector specific ETFS (like INDI, FINI, etc) since I feel that they tilt or bias the portfolio too much. Not ideal for buy/hold. The inclusion of PTXTEN could be seen as breaking this rule, but property is a bit of a special case. Time will tell.
2. Local small holding/large cap index ETFs (like Top40, SWIX) since they are actually not that broad offer limited diversification. Active funds in 100% local equity are doing pretty well (Coronation Top20, Nedgroup Entrepeneur, etc.)

It used to be allowed 3-4 years ago - couple of guys at my office did it. Not sure if anything changed. Just keep in mind that your likelihood of being audited goes up, so get all your supporting documents (for everything) in order if you decide to go ahead with this.